It’s happened to every molecular modeler: hours spent refining a complex structure, carefully adjusting geometry or interaction parameters, only to lose a crucial state after a slip of the mouse or an unexpected action. For those using SAMSON, the integrative platform for molecular design, there’s a simple but powerful tool to help: the History view.
The History view gives you direct access to the timeline of actions performed within a molecular document. More importantly, it allows you to undo and redo modifications, acting as a kind of molecular time machine.
Why This Matters
When working on complex systems—like protein-ligand interactions, quantum chemistry calculations, or large biomolecular assemblies—an errant click or an unintended tool use can irreversibly alter your document. Being able to reverse operations without losing the rest of your manipulations is not a luxury—it’s a necessity.
The good news is that in SAMSON, each document has its own undo/redo history. This makes it extremely helpful for multi-document workflows where you might be editing several molecules simultaneously.
Accessing History
You can open the History view in SAMSON in two ways:
- Via the menu at Interface > History
- Using the keyboard shortcut Ctrl+3 (or Cmd+3 on macOS)
Once open, the History panel shows a list of past actions. Clicking on any item instantly reverts your document to that state. You can jump backward or forward within the action history seamlessly.
Undo/Redo Shortcuts
If you prefer keeping your hands on the keyboard, use:
- Undo: Ctrl+Z / Cmd+Z
- Redo: Ctrl+Y / Cmd+Y
These are standard across most platforms and make the History functionality even more accessible. Note that you can use these within any SAMSON document individually, thanks to the per-document history separation.
Caveats to Know
While immensely useful, there are a few important limitations to keep in mind:
- Not all operations in SAMSON are undoable.
- If you perform a non-undoable operation between undoable actions, you might not be able to properly reverse the previous modifications.
This means it’s a good idea to pay attention to which actions can be undone and to use the History view to navigate your actions rather than relying solely on keyboard shortcuts.
Going Visual
The History view isn’t just a list—it’s a visual one. Each operation is clickable, and sometimes even animated, showing you what happened at that step. This makes retracing your work far less intimidating and much more intuitive, especially for visual thinkers.
This capability can dramatically reduce errors, teach you how you approached modeling tasks, and help with troubleshooting by reexamining past decisions.
Conclusion
The per-document history system in SAMSON is a small but vital feature that can make a big difference in your molecular modeling workflow. Whether you’re adjusting a side chain conformation, constructing a ligand binding site, or scripting custom actions, being able to step back with confidence boosts both productivity and peace of mind.
To learn more, visit the original documentation page.
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download and explore SAMSON at https://www.samson-connect.net.